Information recording apparatus and information recording method

ABSTRACT

An information recording apparatus for recording additional content on a medium on which a title including one or more files is already recorded, includes means for designating a title to be added on the medium; means for transmitting disc package information, the disc package information and unique IDs; means for receiving and additionally recording on the medium the title to be added generated in the content server, file names of files so as not to be the same as the file names of the files constituting the titles already recorded on the medium; means for receiving and additionally recording a new title for display of a menu screen on the medium, which is generated in the content server, so that the title to be added can be selected, on the basis of the disc package information; and means for receiving and additionally recording new disc package information on the medium.

CROSS REFERENCE OF RELATED APPLICATIONS

This application is a Divisional of application Ser. No. 12/937,205filed on Oct. 8, 2010 now U.S. Pat. No. 8,139,451, which is a NationalPhase of PCT International Application No. PCT/JP2009/001736 filed onApr. 15, 2009, which claims the benefit of Japanese Application No.2008-110108 filed in Japan, on Apr. 21, 2008. The entire contents of allof the above applications are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to an information recording apparatus andinformation recording method for recording content supplied by a contentserver onto an optical disc or other recording medium.

BACKGROUND ART

Digital content is now being provided in an environment that is changingfrom physical media such as CD (compact disc) and DVD (digital versatiledisc) media to data distribution through the Internet and othercommunication media. With this change, information recording andreproducing apparatus are becoming capable of more than just reproducingordinary stamped movie packages; it is also possible to download andview digital content through the Internet. For example, in Patentdocument 1, digital content already present on a disc and digitalcontent that has been downloaded from the Internet are linked andreproduced as single content.

-   Patent document 1: Japanese Patent Application Publication No.    2002-369154

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

Because interactive functions, switching of subtitles and sound, menuscreen displays, etc. are required, a format intended for ROM packagesis generally used as the format for downloading and recording moviecontent onto a disc in this way. The ROM package format was created onthe assumption of stamping, so no consideration is given to the(additional) recording of further content onto a disc on which contenthas already been recorded. On the other hand, formats created on theassumption of additional recording lack BD (Blu-ray disc) pop-up menusand other interactive functions, and lack functions for displaying menuscreens prerecorded on the disc, and are therefore unsuited forrecording content such as movies. Another problem is that contentrecorded on a disc in a recording-type format cannot be reproduced by areproduce-only device. The above constraints make it impossible torecord new content on a disc on which downloaded content has alreadybeen recorded, even if there is adequate remaining recording space,which is inconvenient for users. The present invention provides aninformation recording and reproducing apparatus that solves the problemsdescribed above.

Means for Solution of the Problems

An information recording apparatus according to the present inventionrecords additional content on a medium on which a title including aplurality of files is already recorded, the additional content beingprovided by a content server.

The information recording apparatus includes:

means for designating, to the content server, a title to be added;

means for transmitting disc package information to the content server,the disc package information including unique IDs for identifying thetitle already recorded on the medium and the files constituting thetitle;

means for receiving a title for display of a menu screen, including thetitle to be added, for the new disc package, control informationdescribing commands needed to reproduce the titles in the new discpackage, and new disc package information giving unique IDs foridentifying the titles in the new disc package and the filesconstituting the titles, generated in the content server on the basis ofthe disc package information, together with the title to be added; and

means for additionally recording the information received from thecontent server on the medium.

EFFECT OF THE INVENTION

Because the information recording apparatus according to the presentinvention sends the content server disc package information givingunique IDs for identifying the titles already recorded on the medium andthe files constituting the titles, on the basis of the disc packageinformation, the content server can generate a title for display of amenu screen for a new disc package including the additionally recordedcontent. A new disc package including a menu display enabling theadditional title to be selected and reproduced can be obtained byreceiving and recording the title for display of the menu screengenerated by the content server. The additional recording of the titleis carried out in a ROM-compliant data format, so compatibility withreproduce-only devices can be maintained. Content can be added as longas free space is available on the recording medium, so the recordingmedium can be used effectively.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the general structure of aninformation recording and reproducing apparatus according to a firstembodiment and a second embodiment of the present invention.

FIG. 2 is a drawing showing the file structure of an optical discaccording to the first and second embodiments of the invention.

FIG. 3 is a diagram of the structure of a stream, showing the structureof a presentation file in the first and second embodiments of theinvention.

FIG. 4 shows the syntax of a stream information file in the first andsecond embodiments of the invention.

FIG. 5 is a diagram of the structure of a title file in the first andsecond embodiments of the invention.

FIG. 6 shows the syntax of a title file in the first and secondembodiments of the invention.

FIG. 7 shows the syntax of a program file in the first and secondembodiments of the invention.

FIG. 8 shows the file structure in an optical disc in the firstembodiment of the invention.

FIG. 9 shows a menu screen in the first embodiment of the invention.

FIG. 10 shows the overall content downloading system in the first andsecond embodiments of the invention.

FIG. 11 is a drawing of a selection screen by which the user selects atitle to download in the first embodiment of the invention.

FIG. 12 shows the file structure of a disc package constructed by thecontent server in the first embodiment of the invention.

FIG. 13 is a menu screen displayed by the disc package constructed bythe content server in the first embodiment of the invention.

FIG. 14 shows the syntax of the disc package information file in thefirst embodiment of the invention.

FIG. 15 shows a menu displayed by a disc package to which a title hasbeen added in the first embodiment of the invention.

FIG. 16 is a diagram of the structure of a disc package to which a titlehas been added in the first embodiment of the invention.

FIG. 17 shows the syntax of the disc package information file in thesecond embodiment of the invention.

FIG. 18 is a drawing of a selection screen by which the user selectsaudio and subtitles to download in the second embodiment of theinvention.

FIG. 19 is a diagram of the structure of a disc package recorded on anoptical disc in the second embodiment of the invention.

FIG. 20 is a diagram of the structure of a disc package constructed bythe content server in the second embodiment of the invention.

EXPLANATION OF REFERENCE CHARACTERS

1 optical disc, 2 drive, 8 video superimposer, 9 CPU

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment

FIG. 1 is a block diagram showing the structure of the informationrecording and reproducing apparatus 100 in the first embodiment.Reference numeral 1 in FIG. 1 denotes a recordable and reproducibleoptical disc on which certain data (for example, control data needed forcontrol of the information recording and reproducing apparatus 100,movie or music data, and so on) are recorded, and 2 denotes a drive thatreproduces data from the optical disc 1 and records data on the opticaldisc 1. Reference numeral 3 denotes a demultiplexer that separates thedata read by the drive 2 into video data, audio data, graphics data, andinteractive data, 4 denotes an audio decoder that demodulates(hereinafter, decodes) the audio data, 5 denotes a video decoder thatdecodes the video data, 6 denotes a graphic decoder that decodes thegraphics data, 7 denotes an interactive decoder that decodes theinteractive data, and 8 denotes a video superimposer that overlaysimages obtained by decoding graphics data or interactive data and videocreated by the CPU 9 on the video obtained by decoding the video data.Reference numeral 9 denotes the CPU that controls the above elements bysending control commands to these elements, monitoring the status of theelements, etc. Reference numeral 10 denotes an internet connection unitthat connects to an external internet and sends and receivesinformation. Signals such as the control signals output from the CPU 9are omitted in FIG. 1.

Next the reproducing operation will be described.

The drive 2 in FIG. 1 reads data recorded on the optical disc 1 andoutputs the data to the demultiplexer 3. The data output from the drive2 include video data representing images (hereinafter, video) recordedon the optical disc 1, audio data representing sound corresponding tothe video data, graphics data representing images (hereinafter,graphics) overlaid on the video images represented by the video data,and interactive data including button data representing images(hereinafter, buttons) by which the user makes button selections on thescreen and control programs executed when the buttons are selected,multiplexed as packets.

The demultiplexer 3 separates the input data into video data, audiodata, graphics data, and interactive data. The audio data are output tothe audio decoder 4, the video data to the video decoder 5, the graphicsdata to the graphics decoder 6, and the interactive data to theinteractive decoder 7. The demultiplexer 3 performs this separationaccording to identifiers placed at the head of each packet of data.

The audio decoder 4 decodes the input audio data and outputs the decodeddata to an audio output means (not shown). The video decoder 5 decodesthe input video data and outputs the decoded data to the videosuperimposer 8. The graphics decoder 6 decodes the input graphics dataand outputs the decoded data to the video superimposer 8. Theinteractive decoder 7 decodes the input interactive data, outputs thebutton graphics to the video superimposer 8, and outputs the controlprograms to the CPU 9.

The video superimposer 8 overlays the graphics obtained by decoding ofthe graphics data in the graphics decoder 6 and the graphics obtained bydecoding of the button data in the interactive data in the interactivedecoder 7 on the video obtained by decoding of the video data in thevideo decoder 5, and outputs the superimposed data to a display means(not shown).

FIG. 2 shows the file structure of a disc package of the contentrecorded on the optical disc 1. Reference numeral 11 denotespresentation files in which video data, audio data, graphics data, andinteractive data are multiplexed; “STREAM” is the name of a folder inwhich the presentation files 11 are stored. Reference numeral 12 denotesstream information files describing the data structure of thepresentation files 11; “STREAM_IFO” is the name of a folder in which thestream information files 12 are stored. The presentation files 11 andstream information files 12 are in one-to-one correspondence. Referencenumeral 13 denotes title files describing the structure of titles;“TITLE” is the name of a folder in which the title files 13 are stored.Reference numeral 14 denotes a program file including commands neededfor reproducing the title files.

FIG. 3 is a stream configuration drawing showing the structure of apresentation file 11. A stream is made up of fixed-length data unitsreferred to as packets. After the video data, audio data, graphics data,and interactive data are divided into these packet units, they aremultiplexed to form a stream. There is a header area at the beginning ofeach packet; the data in the packet are recognized according to an ID(identification) given in the header. The demultiplexer 3 separatesvideo data, audio data, graphics data, and interactive data byrecognizing these IDs.

FIG. 4 shows the syntax of a stream information file 12. “Start_PTS”indicates the PTS (Presentation_Time Stamp) of the first video frame inthe relevant presentation file 11, and “End_PTS” indicates the PTS ofthe last video frame. “num_of_audio”, “num_of_graphics”, and“num_of_interactive” indicate the quantities of audio data, graphicsdata, and interactive data multiplexed in the presentation file 11. Thefollowing three loop statements (starting with “for”) are repeated“num_of_audio”, “num_of_graphics”, and “num_of_interactive” times; the“packet_ID” entries give the IDs of the packets assigned to therespective streams. Information necessary for random access reproductionis given in “entry_map”. If the video data are encoded according toMPEG-2, the start of a GOP (group of pictures) is equivalent to an entrypoint. In this embodiment, this item indicates which of the packets inthe presentation file 11 are the locations of the start of a GOP.“num_of_entry” is the total number of entry points, “entry_packet_num”is the relative number of packets from the start of the presentationfile 11 to the start of the GOP, and “entry_PTS” is the PTS of the startof the GOP. Because the packets have a fixed length, the relative numberof bytes from the start of the file to the start of the GOP can becalculated by multiplying the value of “entry_packet_num” by the numberof bytes per packet. The information recording and reproducing apparatus100 finds the entry time from “entry_PTS”, then calculates the positionof the entry point on the disc from the corresponding “entry_packet_num”and starts reproduction from there.

FIG. 5 shows the structure of a title. A title is a collection ofcertain intervals in one or more presentation files 11, and may consistof various sets, such as a plurality of intervals in a singlepresentation file 11 or a certain interval in each of a plurality ofpresentation files 11.

FIG. 6 shows the syntax of a title file 13. “num_of_stream” is the totalnumber of presentation files 11 constituting the title; the loopstatement that follows is repeated “num_of_stream” times. A title ismade up of certain intervals in one or more presentation files 11;“stream_name” is the file name of the presentation file 11 to bereproduced; “In_time” and “Out_time” indicate the reproduction startingtime and ending time of the interval to be reproduced in thepresentation file 11. In this embodiment the PTS (Presentation TimeStamp) of the video data is used as “In_time” and “Out_time”.“Start_packet_num” and “End_packet_num” indicate relative numbers ofpackets from the start of the presentation file 11 to the video framesdesignated by “In_time” and “Out_time”. From this information, theinformation recording and reproducing apparatus 100 can determine whatpart of the presentation file 11 to reproduce. “num_of_audio”,“num_of_graphics”, and “num_of_interactive” indicate the number ofvideo, audio, and interactive items to be used in reproduction. Thereare similar parameters in the stream information file 12, but whereasthe parameters in the stream information file 12 indicate the totalnumber of video, audio, and interactive items in the presentation file11, the parameters in the title file 13 differ by indicating the totalnumber of video, audio, and interactive items in the presentation file11 that are used in reproduction. The three following loop statementswill not be described because they are similar to the loop statementsdescribed in FIG. 4. “num_of_sub_stream” is the total number ofpresentation files 11 reproduced together with the stream including thevideo. “sub_stream_name” is the total number of presentation files 11reproduced together with the main stream. “Sync_PTS” is the time atwhich reproduction synchronized with the main stream begins. The rest issimilar to the main stream, so a description will be omitted.

FIG. 7 shows the syntax of a program file 14. “menu_title_file_name” isthe name of a title file that displays the menu displayed when the userpresses the menu key. “num_of_title” indicates the total number ofprograms; the following loop statement is repeated “num_of_title” times.“num_of_command” indicates the total number of programs (commands); thefollowing loop statement is repeated “num_of_command” times.

Next the procedure by which the content of the optical disc 1 isreproduced will be described. FIG. 8 shows an example of the filestructure in the optical disc 1. In the syntax shown in FIG. 6, the“num_of_stream” in each of “00001.title”, “00002.title”, and“00003.title” is set to “1”, and the assigned “stream name” is“00001.strm”, “00002.strm”, “00003.strm”, respectively. “0001.title” isassigned as the “menu_title_file_name” in “Program.cmd”.

FIG. 9 is the menu screen 15 displayed upon reproduction of an opticaldisc 1 on which the files shown in FIG. 8 are recorded. “00001.title” isassociated with “00001.strm” as the files for displaying the menuscreen. A command for reproducing “00002.title” is associated withbutton A 16 and a command for reproducing “00003.title” is associatedwith button B 17. Button A 16 and button B 17 are created from buttondata included in interactive data and the background video image iscreated from video data.

When this optical disc 1 is reproduced by the information recording andreproducing apparatus 100, first the reading of “00001.title” and“00001.strm”, which are related to the display of the menu screen 15,begins. The data that are read are separated by the demultiplexer 3according to the packet IDs specified in “0001.title”, and only thenecessary data are sent to the audio decoder 4, video decoder 5,graphics decoder 6, and interactive decoder 7. The images decoded by thevideo decoder 5 are combined with the images decoded by the graphicsdecoder 6 and the images decoded by the interactive decoder 7 in thevideo superimposer 8 and output.

If the user selects button A 16, “00002.title” is selected, and thecorresponding “00002.strm” is read from the optical disc 1 andreproduced. If button B 17 is selected, “00003.title” is selected, andthe corresponding “00003.strm” is read from the optical disc 1 andreproduced. When the user has selected a title and reproduction of theselected title has been completed, the CPU 9 reads a commandcorresponding to the reproduced title from “Program.cmd” and executesit. If, for example, the command specifies a return to the menu, thefiles associated with display of the menu screen are read and the menuscreen is displayed. If the command specifies the reproduction ofanother title, the files associated with that title are read and thetitle is reproduced.

The procedure for recording content downloaded from the Internet on theoptical disc 1 in the format above will be described below.

FIG. 10 shows the overall content downloading system. Reference numeral19 in FIG. 10 denotes an Internet connection, 18 denotes a contentserver connected via the Internet connection, and 100 denotes theoverall information recording and reproducing apparatus shown in FIG. 1.The internet connection unit 10 in FIG. 1 is linked to the Internetconnection 19. The CPU 9 receives data for display of a Web browser fromthe content server through the internet connection unit 10, createsgraphics according to the data, outputs the graphics to the videosuperimposer 8, uploads data recorded on the optical disc 1 to thecontent server 18 connected to the Internet connection, downloads datain the content server 18 to the information recording and reproducingapparatus 100, and performs various other processing.

FIG. 11 shows a guidance screen that is constructed by the processing,in the CPU 9 and video superimposer 8, of data transmitted from thecontent server 18 connected via the Internet 19, and is displayed by aWeb browser. When the user, following this guidance screen, selectscontent to be additionally recorded, the corresponding data aredownloaded and the new content is added to the optical disc 1. Buttons19-22 show a list of titles that the user can select; here there arefour selectable titles. To select movie A and movie C, the user uses aninterface (not shown) to designate buttons 19 and 21. When buttons 19and 21 are designated, but content server 18 constructs a disc packageincluding movie A and movie C as titles.

FIG. 12 shows the file structure of the disc package constructed in thecontent server 18. The title files 13 include “00001.title”, which is amenu title, “00002.title”, which corresponds to movie A, and“00003.title”, which corresponds to movie C. The presentation files 11include “00001.strm” corresponding to “00001.title”, “00002.strm”corresponding to “00002.title”, and “00003.strm” corresponding to“00003.title”. The stream information files 12 include three files“00001.ifo”, “00002.ifo”, “00003.ifo” corresponding to “00001.strm”,“00002.strm”, and “00003.strm”. The program files 14 include a discpackage information file “Package.ifo”, described below, in addition to“Program.cmd”. FIG. 13 is a menu screen for the disc package includingmovie A and movie B that has been constructed by the content server 18.Movie A is reproduced if button 23 is selected, and movie C isreproduced if button 24 is selected. When the construction of the discpackage information file is completed in the content server 18, theinformation recording and reproducing apparatus 100 downloads the discpackage information file and writes it on the optical disc 1.

Next the procedure for adding a new title (movie D) to the optical disc1 on which movie A and movie C have been recorded as explained abovewill be described. As already noted, a title for display of a menuscreen is included in the disc package, so when movie D is added, atitle for a new menu screen including the additional movie D must beconstructed. For this purpose, it is necessary to have means by whichinformation about the titles already recorded on the optical disc 1 canbe known at the content server 18.

FIG. 14 shows the syntax of the disc package information file“Package.ifo” shown in FIG. 12. “num_of_title” is the total number oftitles recorded on the optical disc. The following “for” loop isiterated “num_of_title” times. “title_name” indicates the file name of atitle, and “title_identifier” is the unique ID of the title. This uniqueID may be a series of numbers identifying the title from a title list inthe server, or text information giving the name of the title directly.“num_of_stream” is the number of stream files constituting the title;the following “for” loop is repeated “num_of_stream” times. “streamname” indicates the file name of a stream. Sending the disc packageinformation file to the content server 18 enables the content server 18to recognize information about the titles already recorded on theoptical disc 1 on which the new title is to be recorded.

When the user selects movie D on the guidance screen in FIG. 11, theinformation recording and reproducing apparatus 100 is asked by thecontent server 18 to upload a disc package information file. Theinformation recording and reproducing apparatus 100 uploads the discpackage information file in accordance with this request. The contentserver 18 learns from the “title_identifier” items in the disc packageinformation file that movie A and movie C are already recorded on theoptical disc 1, and constructs a title for the display of a new menuscreen including movie A, movie C, and the additional title (movie D) asin FIG. 15.

FIG. 16 shows the structure of the disc package constructed in thecontent server 18 when movie D is selected as content to be added to anoptical disc 1 on which movie A and movie C have already been recorded.From the “title_identifier”, “title_name”, and “stream_name” in the discpackage information file “Package.ifo” the menu screen title of theoptical disc 1 is seen to include “00001.strm”, “00001.ifo”, and“00001.title”. The new menu screen title is configured by updating thefiles “00001.strm”, “00001.ifo”, and “00001.title”. Similarly, it can beseen from the disc package information file that files 00001 to 00003are already in use on the optical disc 1, so the file names“00004.strm”, “00004.ifo”, and “00004.title”, which are not used yet,are assigned to movie D. The files constituting movie A and the filesconstituting movie C, which are already recorded on the optical disc 1,are assigned their existing file names. The two files “Program.cmd” and“Package.ifo” are newly updated in order to add the new title. When thenew disc package has been constructed at the content server 18,downloading to the information recording and reproducing apparatus 100begins. The downloaded files are the files constituting movie D, thefiles constituting the title for menu screen display, and “Program.cmd”and “Package.ifo”. The information recording and reproducing apparatus100 overwrites the files “00001.strm”, “00001.ifo”, and “00001.title”constituting the title for menu screen display, and newly writes thefiles “00004.strm”, “00004.ifo”, and “00004.title” constituting movie D.The newly configured “Program.cmd” and “Package.ifo” are alsooverwritten. A disc package including movie A, movie C, and movie D isrecorded on the optical disc 1 by the above procedure.

As described above, disc package information indicating the titleinformation already recorded on the optical disc 1 is provided in theprogram files 14; this information is transmitted to the content server18, so that the content server 18 can recognize the title informationalready recorded on the optical disc 1, and if a new title is to beadded, can construct a disc package having a title for display of a newmenu screen that includes the additional title. A disc package thatpermits all the movie titles, including movie A, movie C, and movie D,to be selected from the menu screen and reproduced can be obtained bydownloading the data of the title for display the new menu screen andthe title being added from the content server 18 and recording the dataon the optical disc 1. The additional recording of titles is carried outin a ROM-compliant data format, so compatibility with reproduce-onlydevices can be maintained. Content can be added as long as free space isavailable on the recording medium, so the recording medium can be usedeffectively.

Second Embodiment

The adding of a new title was described in the first embodiment, but theadding of part of a title, instead of an entire title, is alsocontemplated. Exemplary cases are the later addition of new audio orsubtitle content to a single title. In the second embodiment, a methodof updating part of a title will be described.

FIG. 17 shows the syntax of a disc package information file used toupdate part of a title. Differing from the disc package information fileshown in FIG. 14, loop statements for recognition of the audio data,graphics data, and interactive data present in the presentation file 11are added below “num_of_sub_stream”. “num_of_sub_stream” is the totalnumber of substreams included in the title; the following loop statementis repeated “num_of_sub_stream” times. “num_of_sub_audio”,“num_of_sub_graphics”, and “num_of_sub_interactive” are the total numberof audio data, graphics data, and interactive data items present in thepresentation file 11. The following three loop statements are repeated“num_of_sub_audio”, “num_of_sub_graphics”, and “num_of_sub_interactive”times. “sub_audio_identifier”, “sub_graphics_identifier”, and“sub_interactive_identifier” are unique IDs expressing the content ofthe audio data, graphics data, and interactive data.

FIG. 18 is the guidance screen configured by processing, in the CPU 9and video superimposer 8, of the data transmitted from the contentserver connected via the Internet connection. Following the guidance onthis screen, the user performs operations to select the audio orsubtitles that the user himself or herself wants to add, download thedata, and record the data on the optical disc 1. In FIG. 18, the usercan select graphics data for Japanese or Korean subtitles with buttons28 and 29, and audio data for an English or Korean soundtrack withbuttons 30 and 31.

FIG. 19 shows the file structure of the disc package already recorded onthe optical disc 1. This disc package includes two movie titles (movie Aand movie B), and movie A has a graphics data substream for display ofsubtitles. Japanese audio is multiplexed into the main stream of movieA, without subtitles. The subtitles overlaid on movie A are in English.In the presentation files 11 in FIG. 19, “00001.strm” is the file of atitle for menu display, “00002.strm” is the file for movie A, “00003.strm” is the file for movie B, and “00004.strm” is a graphics file fordisplay of subtitles overlaid on movie A. In the stream informationfiles 12, “00004.ifo” is the file corresponding to “0004.strm”. In thetitle files 13, “00001.title” corresponds to the menu screen title,“0002.title” to the movie A title, and “00003.title” to the movie Btitle. Except for “00004.strm” and “00004.ifo”, the title and filerelationships are as in the first embodiment (FIG. 12). In the discpackage information file “Package.ifo” in the program files 14, a“sub_audio_identifier” and “sub_graphics_identifier” indicate thatJapanese audio is present in the main stream file “00002.strm” of movieA, and English subtitles are present in the sub stream file“00004.strm”.

The procedure when the user selects Korean subtitles and English audiofor movie A on the guidance screen in FIG. 18 will now be described.When the user selects Korean subtitles with button 29 and English audiowith button 30, a request for the uploading of a disc packageinformation file is made from the content server 18 to the informationrecording and reproducing apparatus 100. Obeying this request, theinformation recording and reproducing apparatus 100 uploads the discpackage information file. From the disc package information file, thecontent server 18 sees that there is already one sub stream for title 1,that Japanese audio is present in “00002.strm”, and that Englishsubtitles are present in “00004.strm”. When the audio or subtitles theuser is attempting to download are already present on the optical disc1, the user is advised that downloading is not necessary and downloadingis not executed. After it has been confirmed that the sub stream to beadded is new, the content server 18 constructs a new disc package. Firstit constructs a sub stream in which the graphics data for the Koreansubtitles and the audio data for the English soundtrack, which are to benewly added, are multiplexed together with the graphics data of theEnglish subtitles already present as a sub stream of movie A. The newlyconstructed sub stream is recorded by updating the sub streampresentation file “00004.strm” and stream information file “00004.ifo”already present on the optical disc 1. Next, since new graphics data andaudio data have been added, the title file “00002.title” of movie A isupdated. The disc package information file “Package.ifo” is similarlyupdated. FIG. 20 shows the configuration of the disc package constructedat the content server 18.

When the new disc package has been constructed by the content server 18,the downloading of files to the information recording and reproducingapparatus 100 begins. The downloaded files are the four newly updatedfiles: “00004.strm”, “00004.ifo”, “00002.title”, and “Package.ifo”.Since the only changes are the addition of audio and subtitles to movieA, no updates are carried out for the menu screen and movie B.

In the second embodiment, it is possible to add only audio or onlysubtitles by adding a “sub_audio_identifier”, “sub_graphics_identifier”,and “sub_interactive_identifier”, which are information identifyingaudio data, graphics data, and interactive data included in the title,to the disc package information file.

1. An information recording apparatus for recording additional contenton a medium on which a title including one or more files is alreadyrecorded, the additional content being provided by a content server, theinformation recording apparatus comprising: means for designating, tothe content server, a title to be added on the medium; means fortransmitting disc package information, which is read from the medium, tothe content server, the read disc package information including a uniqueID to be used by the content server for identifying all titles alreadyrecorded on the medium; means for receiving and additionally recordingon the medium the title to be added generated in the content server,file names of files constituting the title to be added being defined inthe title to be added, on the basis of the disc package information, soas not to be the same as the file names of the files constituting thetitles already recorded on the medium; means for receiving andadditionally recording a button of a menu screen for display of the menuscreen generated in the content server so that the title to be added canbe selected on the basis of the disc package information; and means forreceiving and additionally recording new disc package information on themedium, wherein the new disc package information identifies the title tobe added generated in the content server and the button of the menuscreen for display of the menu screen generated in the content server,and provides file name information of each file in the title to beadded.
 2. A method implemented in an information recording apparatus forrecording additional content on a medium on which one or more titleseach including one or more files are already recorded, the additionalcontent being provided by a content server, the method comprising:transmitting to the content server a designation of a title to be addedto the medium; reading from the medium disc package information, andtransmitting the read disc package information to the content server,the read disc package information including a unique ID identifying tothe content server all titles already recorded on the medium; receivingthe title to be added from the content server, the title to be addedcomprising files whose file names are defined on the basis of the readdisc package information so as not to be the same as the file names ofthe files constituting the titles already recorded on the medium;receiving from the content server a button of a menu screen to bedisplayed so that the title to be added can be selected in addition tothe files already recorded on the medium; receiving from the contentserver new disc package information, which identifies the title to beadded and the button of the menu screen, and provides file nameinformation of each file in the title to be added; and recording thetitle to be added, the button of the menu screen, and the new discpackage information on the medium in addition to the titles, the menuscreen, and the disc package information already recorded on the medium.